Casting and in the process for its manufacture



Aug. 19 1924. 1,505,401

E; MAYER CASTING AND IN THE PROCESS FOR ITS MANUFACTURE Filed March 14,1922 .Z nrewfar;

iJ le ef Patented Aug. 19, 1924;.

a i r tea e401 rnr FF C nrennsrnarnn, or anrwnnr, lanternn:

CASTING AND IN THE PROCESS FOR ITS MANUFACTURE.

Application filed March 1%, 1922. Serial No. 543,754,

lvlanuttacture; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame, reference being had to the accompanying drawings, and to lettersor figures of reference marked therein, which form a part of thisspecification. I

In some castings in iron or steel it is of frequent occurrence to finddefects due to porous places, unequal shrinkage and accidentalblow-holes, which necessitates scrapping the castings even when thelatter appear good and uniform and well moulded on careful visualinspection so that it is only after being machined and being subjectedto pressure tests that the castings show want of tightness.

These defects are particularly serious and objectionable in the case ofcertain articles such as the cylinders for motor-car, aeroplane engines,and locomotives, hydraulic piping and presses, etc.

The present invention has now for its object to obviate the abovementioned de-' fects.

This object is efiected by joining to the mass of the castings, inpouring the metal a solid plate or sheet of metal of such shape anddimensions that the walls of the castings which are strengthened orrendered tight thereby are thus composed partly of ordinary castingmetal and partly of rolled or drawn sheet of metal having a highermelting point, this part of rolled sheet constituting one or more of thewalls of the castings.

Owing to the temperature to which this sheet of metal is subjectedduring the pouring operation an intimate union takes place between thetwo parts of the castings.

The walls of the castings thus produced are rendered fluid-tight and arestrengthened owing to the pressure of this sheet of metal.

On the other hand the presence of this rolled or drawn sheet of metalacts, during the pouring operation, chemically and phy ically upon thequality of the casting also metal that is situated in its immediatevicinity, For instance the casting metal in eontact withthe sheet ofsoft steel becomes decarburizedand the grain of the casting metal isthereby rendered finer so that the casting metal becomesstronger andmore fluid-tight. i

I The sheets of metal are usually rolled and of flat, tubular, or dishedform, or drawn in the form of tubes, and they may be covered with asuitable metal or coating. 7

For. instance,

they .may be previously tinned.

The shape of these "sheets of metal de-.

pends necessarily on the shape of the walls of the casting. Intheapplication of this invention to a cylindrical article" (enginecylinder, press cylinder,'pipe, etc.) the sheet "of metal consistssimply ofa tube or'of a'metal sheet bent in theform of a tube.

'lVhen the invention is applied on the contrary to walls of morecomplicated form, such as cylinder jackets, valve chests, etc,

the'sliape of the metalplate is usually produced by dishing orprofile-shaping.

I It is to be note'd that the process, according to the invention, whichhas {as result the obtaining of castings having walls of mixedcomposition, comprising a part of cast-iron and a part ofmetal sheet,this latter being placed on one of the faces of the walls, isessentially different to the process which consists in obtainingcastings having a sheet of metal placed near the middle of the'wall,this sheet serving to the strengthening of the casting.

The accompanying drawings illustrate by way of example the positioningof these metal sheets in the case of an internal combustion enginecylinder,uand in the case of a tube. v

Figure 1 is asection of an internalcombustion engine cylinder and'otherelements forming the casting. I

Figure 2 is a section of a tube. V

As shown in Figure 1, the arrangement is as 'follows: i

A tubular metal sheet 1 insertedin the cylindrical portion of the enginecylinder.

A dished. metal sheet 2 inserted in the head.

A cylindrical metal sheet 3 arranged around the suction pipe. I

A metal sheet 4 arranged around the exhaust valve chest.

A cylindrical metal sheet 5 arranged around the socket for the sparkingplug.

It is to be'noted that according to circumstances, according to thenature of the metal, and the quality of the castings to be produced itis optional to use plates 01- sheets or tubes of any suitable shape andmaterial, thesenietal sheets being joined atterwards to the Walls of thecasting.

In the case of Figure 2, a plate 6 is pro vided which is placed on theouter surface of the casting tube, and another plate 7 which isarrangedon the inner surface of the said tube.

It is to be noted that in thecase of the pouring of castings having acomplicate form as cylinder-blocks for internal combustion engines (Fig.l). or other pieces presenting variable thicknesses, the use of'metalsheets, according to the present invention, prevents the contraction ofthe cast iron and consequently the defects of leakage on the spots Wherethe variation of the thickness of said pieces is notable.

In considering, by Way of example, the spot 8, Where the outer surfaceof the coolin}: jacket 9 is joined to the cylinder properly so called.The founders know that by the cooling of a casting, it is specially onthis spot that the defects of leakage are produced, by the formation ofcracks and by obtaining cast-iron of porous constitu tion.

By the interpositionof a metal sheet according to the invention. thefollowing advantages are specially obtained (1) The cylinder properly socalled is poured as having only Wall of uniform thickness, whereby thepouring OPQIHJJCIOHQS assured to be particularly regular, that is tosay, Without swells, erks and shocks.

The inconveniences of the contraction, produced by cooling on the spotsas 8, where the variation of section. is a sudden one, are prevented bythe fact that the overthickness is divided into two parts by the metalsheet, in such a manner that the con traction on these spots isproduced. as if there were on said spots t vo distinct pieces of normalthickness.

Claims.

' l. A casting having relatively thick and relatively thin portions, inconiliiination with ietal sheets, the sheets being positioned on thesurfaces of the relatively thin portions, and embedded in the casting inthe relatively thick portions, so as to be enveloped by.

the casting, the changes from the surface positioning to the embeddedpositioning occurling at points Where there is an abrupt change ofthickness in the casting.

2. A casting according to claim 1, the changes from said surfaceniolding,to said envelopnient by the cast metal, occurring at pointsWhere there is an abrupt change of thickness in the casting.

In testimony whereof I aliix my signature in presence of two Witnesses.

Witnesses LEONARD LEVER, v Gnoncns VANDER HAEGHEN.

ERNEST MAYER.

